Abstract
Pair density waves (PDW) are novel forms of superconducting states characterized by periodically modulated superconducting order parameter. One outstanding challenge in condensed matter physics is to elucidate how intrinsic PDW order may emerge in electronic systems with strong correlations. In this talk, we will argue that PDW may develop in the exotic scenario wherein a system with uniform pairing would exhibit negative superfluid weight/stiffness (which promotes a tendency towards superconducting phase modulations). Focusing on strong-coupling, multiband superconductors, we propose two routes to realize PDW order, one leveraging quantum geometric effects, and the other utilizing simple interband Cooper pairing between two oppositely dispersing bands. We will present both phenomenological analysis and results from advanced density-matrix-renormalization-group calculations to confirm this robust pathway to PDW order.
Anyone interested is welcome to attend.